In the conventional method for measuring mass flow rate of media moving through a single conduit under a flexural vibration or through a pair of conduits under a relative flexural vibration therebetween, the phase angle difference between two electrical signals respectively representing the flexural vibration of the conduit at two sections located symmetrically about the midsection of the conduit is measured and the mass flow rate of the media is determined from the phase angle difference by using an empirically determined mathematical relationship therebetween, or the mass flow rate is determined as a function of other parameters directly or indirectly related to the phase angle difference.